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Data adaptive mixing automatic retransmitting method for orthogonal frequency division multisystem

A technology of hybrid automatic retransmission and orthogonal frequency division, which is applied in multi-frequency code systems and uses return channels for error prevention/detection, etc., can solve problems such as inability to obtain frequency diversity gain, increase decoding reliability, reduce Bit error rate and transmission delay, the effect of transmission performance optimization

Inactive Publication Date: 2007-05-02
TSINGHUA UNIV
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Problems solved by technology

In the previous Chase combined Type-III hybrid ARQ, the sending end adopts the same symbol transmission order for each retransmission, so it can only obtain a certain time diversity gain but cannot obtain more frequency diversity gain

Method used

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  • Data adaptive mixing automatic retransmitting method for orthogonal frequency division multisystem
  • Data adaptive mixing automatic retransmitting method for orthogonal frequency division multisystem
  • Data adaptive mixing automatic retransmitting method for orthogonal frequency division multisystem

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Embodiment Construction

[0030] The data self-adaptive hybrid automatic retransmission method for the OFDM system proposed by the present invention first reads the information bits from the user data source, and performs cyclic redundancy check coding; Coding and modulation to form K modulation symbols, and store data according to the retransmission indication information of the receiving end; perform symbol reorganization on the above stored data according to the output channel parameters at time t-1 in the system; perform inverse Fourier transform on the above recombination, Get the time domain signal of the stored data, add a cyclic prefix to it and send it; receive the above data, remove the cyclic prefix, and perform Fourier transform to obtain the received data symbol in the frequency domain; output the channel according to the t-1 time of the system Parameters, performing adaptive deinterleaving corresponding to the symbol recombination at the sending end on the above-mentioned received data sig...

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Abstract

The present invention relates to a data adaptive mixed automatic retransmission method for orthogonal frequency division multiplexing system, belonging to the field of mobile communication technology. Said method includes the following steps: firstly, reading-in information bit, coding, modulation and storage; according to the output channel parameter making symbol reformulation for stored data, making OFDM demodulation, according to output channel parameter of system making adaptive deinterleaving for received data signal so as to obtain reduced data symbol, then making soft demodulation of data, combination of data and decoding to obtain information bit flow.

Description

technical field [0001] The invention relates to a data adaptive hybrid automatic retransmission method used in an orthogonal frequency division multiplexing system, belonging to the technical field of mobile communication. Background technique [0002] In recent years, with the rapid development of high data rate and reliable service requirements, the hybrid automatic repeat request (hereinafter referred to as hybrid ARQ) protocol has become one of the key technologies of the Beyond 3G mobile communication system. The hybrid ARQ protocol effectively combines forward error correction code (hereinafter referred to as FEC) technology and ARQ protocol, so it is not only more reliable than FEC, but also can obtain a higher pass rate than ARQ. Hybrid ARQ technology has the above advantages, so it is widely used in non-real-time data services. [0003] Hybrid ARQ provides precise code rate adjustment based on channel conditions, can automatically adapt to instantaneous channel con...

Claims

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Application Information

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Patent Type & Authority Patents(China)
IPC IPC(8): H04L1/18H04L27/26
Inventor 程锦霞周世东李云洲姚彦王京粟欣肖立民许希斌
Owner TSINGHUA UNIV
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